Aaron's Magnificent Crossword Puzzle

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Across
  1. 2. Protagonist's best friend
  2. 3. German dictator
  3. 5. The author of the book
  4. 6. Code name for the German's most dangerous invention yet.
  5. 7. Protagonist and Irish spy.
  6. 8. The capital of Germany and main setting in the book
Down
  1. 1. Where the protagonist came from.
  2. 4. World War l veteran and professor.